Yamashiro Tsuneo, Tsubakimoto Maho, Nagatani Yukihiro, Moriya Hiroshi, Sakuma Kotaro, Tsukagoshi Shinsuke, Inokawa Hiroyasu, Kimoto Tatsuya, Teramoto Ryuichi, Murayama Sadayuki
Department of Radiology, Graduate School of Medical Science, University of the Ryukyus, Nishihara, Okinawa, Japan.
Department of Radiology, Shiga University of Medical Science, Otsu, Japan.
Int J Chron Obstruct Pulmon Dis. 2015 Sep 25;10:2045-54. doi: 10.2147/COPD.S87588. eCollection 2015.
The purpose of this study was to evaluate the feasibility of continuous quantitative measurement of the proximal airways, using dynamic ventilation computed tomography (CT) and our research software.
A porcine lung that was removed during meat processing was ventilated inside a chest phantom by a negative pressure cylinder (eight times per minute). This chest phantom with imitated respiratory movement was scanned by a 320-row area-detector CT scanner for approximately 9 seconds as dynamic ventilatory scanning. Obtained volume data were reconstructed every 0.35 seconds (total 8.4 seconds with 24 frames) as three-dimensional images and stored in our research software. The software automatically traced a designated airway point in all frames and measured the cross-sectional luminal area and wall area percent (WA%). The cross-sectional luminal area and WA% of the trachea and right main bronchus (RMB) were measured for this study. Two radiologists evaluated the traceability of all measurable airway points of the trachea and RMB using a three-point scale.
It was judged that the software satisfactorily traced airway points throughout the dynamic ventilation CT (mean score, 2.64 at the trachea and 2.84 at the RMB). From the maximum inspiratory frame to the maximum expiratory frame, the cross-sectional luminal area of the trachea decreased 17.7% and that of the RMB 29.0%, whereas the WA% of the trachea increased 6.6% and that of the RMB 11.1%.
It is feasible to measure airway dimensions automatically at designated points on dynamic ventilation CT using research software. This technique can be applied to various airway and obstructive diseases.
本研究的目的是评估使用动态通气计算机断层扫描（CT）和我们的研究软件对近端气道进行连续定量测量的可行性。
在肉类加工过程中取出的猪肺，通过负压气缸在胸部模型内通气（每分钟8次）。这个模拟呼吸运动的胸部模型由320排面积探测器CT扫描仪进行扫描，作为动态通气扫描约9秒。获得的容积数据每0.35秒重建一次（共8.4秒，24帧），作为三维图像并存储在我们的研究软件中。该软件自动在所有帧中追踪指定的气道点，并测量横截面管腔面积和壁面积百分比（WA%）。本研究测量了气管和右主支气管（RMB）的横截面管腔面积和WA%。两名放射科医生使用三点量表评估气管和RMB所有可测量气道点的可追溯性。
判断该软件在整个动态通气CT过程中令人满意地追踪了气道点（气管平均评分为2.64，RMB平均评分为2.84）。从最大吸气帧到最大呼气帧，气管的横截面管腔面积减少了17.7%，RMB减少了29.0%，而气管的WA%增加了6.6%，RMB增加了11.1%。
使用研究软件在动态通气CT上的指定点自动测量气道尺寸是可行的。该技术可应用于各种气道和阻塞性疾病。
